1. Field of the Invention
The present invention relates to an electronic equipment which is operable by a plurality of control programs even if initial settings required by the respective control programs are different.
2. Related Background Art
In the electronic equipment whose operation is controlled by a microprocessor, it is not rare to provide a non-volatile RAM (NVRAM) or an electrically erasable programmable ROM (EEPROM) instead of a dip switch and retain various initial settings necessary for the initialization upon power-on in the RAM in order to attain quick initialization at the power-on.
Since the stored content of the NVRAM is not destroyed by the power-off, the NVRAM may function as the dip switch and it is cheaper than the dip switch. Further, the stored content may be altered by a panel switch or an instruction from a host computer.
In a printer which is an example of the electronic equipment, data such as a communication protocol, an architecture of equipment control commands, character font of print characters and an architecture of character codes are stored in the NVRAM as the initial settings and they are used for the initial setting at the power-on.
However, in the past, the NVRAM has been used for the initial setting at the power-on in only an electronic equipment in which the microprocessor performs only one or a very limited range of control functions.
Where a control program is loaded in a program cartridge which can be plugged into the electronic equipment so that the electronic equipment may have multi-functions and multi-applications by a plurality of different control programs, the following problems arise in the initial setting of the control programs at the power-on.
The initial values required to be stored in the NVRAM in order to permit rapid initialization at the power on are not always the same for the respective control programs. Rather, it is normal that the control programs differ from each other to some extent. For example, some programs may need totally different information items or the initial values may be different even if the items are the same. Because of a limited capacity of the NVRAM, it is impossible, as the number of control programs increases, to store all initial values for all control programs which may be used, in the NVRAM.
Further, it is more difficult to store the initial values for control programs which will be developed in the future, at the time of the development of the electronic equipment.